Cysteine-flanked peptides are uniquely designed to bind ionically to plasmid DNA and undergo a template polymerization via formation of disulfide bonds 1. Thereby, relatively short cationic peptides can form long polypeptides that transiently stabilize DNA condensates until they reach the reducing environment of the endosome which triggers disulfide bond reduction and DNA release. Using an orthoganol protection scheme, we have previously synthesized cysteine-flanked glycopeptides and PEG-peptides and used these to demonstrate transient gene expression in vivo 2,3.